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JRSJKD
10-17-2001, 02:28 PM
Check this out, and make sure your not standing too close to a guy with a PMI:

http://www.pminetwork.com/gunadvise.htm

I didn't know that you could get CO2 to exceed 3000psi. Surely the burst disk would have gone before that. Sounds to me like the bodies are just weak. Scary either way.

Junior

tooslow
10-17-2001, 02:53 PM
The problem really isn't with the gun.It is designed to withstand pressure in the 3000 psi range. The problem was actually with the burst discs in some BE tanks that were being sold with one version of this gun at a large mass market retailer in the US. When one of these tanks were overfilled or heated up, the burst disc would fail to blow, putting excessive psi's into the gun, which has a plastic body. There were only 2 actual cases of failure and no one was injured. But, PMI being the responsible company that they are, recalled all Trracer S/A variants. The only modification to the gun is the addition of a burst disc assembly at the ASA, between the gun and the tank. That way it does not matter if your tank is faulty, the disc in the adapter will blow if pressures get too high.

JRSJKD
10-17-2001, 02:58 PM
This may sound like a stupid question, but how high can the pressure get in a CO2 tank. I didn't think it could get as high a 3000psi.

Junior

tooslow
10-17-2001, 03:03 PM
No, that's not a stupid question at all.

CO2 is usually in a liquid state in a tank and runs in the neighborhood of 800 psi. But, at around 82 degrees CO2 automatically converts to a gaseous state. Now, the gas will have a higher pressure that the liquid. If the tank is not overfilled or too hot, the pressure will be around 1800 psi. But, overfill or over heat the tank and the pressure will rise. That is why most burst discs are set to burst around 2500 - 3000 psi. Hope this helps.

JRSJKD
10-17-2001, 03:07 PM
TOOSLOW, thanks. Was aware of most of that but thought that the pressure never rose much above 1200psi even when overheated. Thanks for the info.

junior

tooslow
10-17-2001, 03:10 PM
No problem:) Glad to help. If anyone wants more detailed info on CO2, they can contact any distributor of compressed gasses, such as Praxair, and request a MSDS. They will usually send you one for free. Come to think of it, I think Praxair has MSDS's on their website for downloading....

tooslow
10-17-2001, 03:15 PM
Yup, they do. Here's the link for anyone who's interested.

http://www.praxair.com/praxair.nsf/HTMLMSDSsByTitle?OpenView

Webmaster
10-17-2001, 04:07 PM
Ok - I dont believe its a problem of the tank, its a problem with the gun. If for what ever reason a gun is left in the sun, the CO2 in the VALVE CHAMBER, can raise high enough to break the gun. On reason I would never make the valve area out of plastic...

Ityl
10-17-2001, 08:58 PM
Burst disks are meant to blow at 1800 to 2200. I've never seen the pressure run above like 1200-1300.

tooslow
10-17-2001, 09:04 PM
Burst discs, which are nothing but thin discs of metal, are designed to burst at a particular pressure. the higher the pressure, the thicker the disc. Most of the CO2 tanks that are currently on the market have 2500 psi discs in them. At least most of the tanks that I have sold have, anyway. I was not aware that anyone was using a 1800 psi disc.